Blink bidi code does not have a L1 implementation, all the L1 logic is done by
RenderBlockFlow::handleTrailingSpaces in the rendering code.
The purpose of this patch is moving the handleTrailingSpaces logic to 
BidiResolver.
 
[1] http://www.unicode.org/reports/tr9/#L1

BUG=316409

Review URL: https://codereview.chromium.org/119853004

git-svn-id: svn://svn.chromium.org/blink/trunk@164557 bbb929c8-8fbe-4397-9dbb-9b2b20218538